From a seated position with straight legs, bend the right knee and bring the right foot to the left thigh, making a L shape with your femur bones.
Draw the right heel to the right groin.
Lift the hips up to sit on the heel. You can bring your torso forward and plant your hands in front of you to lift your hips.
Lengthen the spine and fold forward over the inside of the left (straight) leg. You should feel a stretch on the side of the bent leg. Grab the sides of the foot or the left wrist with the right hand.
Form tips
Don't close the angle between your legs as you sit on the heel. Aim for 85°.
The foot is in the same position as Janu sirsasana A, with toes pointing forward.
If this feels uncomfortable, you can do the version seated on a block.